You probably don’t want to adjust the gamma. Most websites, digital photos, etc, are prepared with a 2.2 gamma in mind. Even macs, which have traditionally been a 1.8, have moved to 2.2 to join their PC counterparts.
I think you want to look at adjusting the colour temperature, which will take the edge off those whites and warm the picture up.
Another program I’m using that I find quite useful is f.lux, which will automatically warm the picture up at night when you are in dimmer and warmer lighting, and cooler during the day when you have brighter lighting. This can help reduce eyestrain at night, and also help you get to bed easier, believe it or not.
Check it out here:
http://www.stereopsis.com/flux/